Field of the Invention
The present invention relates to a communication relay device, a non-transitory readable recording medium and a communication relay method. The present invention more specifically relates to a technique of controlling a communication path established with an application server when communications between the application server and an image processing device are relayed.
Description of the Background Art
Recently, application servers have been installed on a cloud on an internet, and they provide with a variety of application services (cloud services). As users have an access to the application services at anytime from anywhere, those application services are convenient for the users. Image processing devices such as MFPs (Multifunction Peripherals) installed at places such as offices capable of executing jobs by working in concert with the application servers have been introduced along with the popularization of the application services. This known technique is introduced for example in Japanese Patent Application Laid-Open No. JP 2013-51597 A. According to this known technique, the system that causes the image processing device and the application server operate in concert with each other is capable of making the image processing device execute a print job by downloading data such as a document or an image stored in the application server, or upload image data generated by a scan job by the image processing device to the application server.
The aforementioned system includes a communication relay device that establishes a communication path with the application server in a local network environment in which the image processing device is installed. The communication relay device is installed in order to realize a transmission of job data to the image processing device from the application server if a job is created at the application server. The communication relay device accesses a connection mediation server installed on a cloud on an internet at its startup, thereby establishing permanent connection. After the permanent connection is established, a job that requires the communication with the image processing device may be created at the application server. In this case, the application server sends a communication request with the communication relay device to the connection mediation server. In response to receiving the communication request, the connection mediation server sends the communication request to the communication relay device on the local network over the communication path that maintains the permanent connection. After receiving the communication request issued by the application server from the connection mediation server, the communication relay device accesses the application server on the internet and establishes the communication path with the application server. As a result, the communication path is established between the application server and the communication relay device. The application server then sends the job data to the communication relay device over the communication path, and the communication relay device forwards the job data to the image processing device.
It is assumed that the job that requires the communication with the application server is created at the image processing device on the local network. In this case, the image processing device sends the job data corresponding to the job to the communication relay device. After receiving the job data from the image processing device, the communication relay device identifies the application server which is the connecting destination, and connects to the application server on the internet over the local network. The communication path with the application server is then established. The communication relay device forwards the job data received from the image processing device to the application server over the communication path established with the application server.
The communication relay device is installed in the local network environment so that two-way communication between the application server and the image processing device is allowed. Even when the job is created at either the application server or the image processing device, the job data corresponding to the job is allowed to be sent and received between the application server and the image processing device.
The conventional system that makes the image processing device and the application server work in concert with each other, however, requires generation of a new communication path for the communication relay device to transmit and receive the job data of the job every time the job is created at the application server or the image processing device. Thus, the number of the communication paths that should be managed by the application server is increased, resulting in increased load on the application server. Especially the application server is connected to a number of the local networks. If the communication path is established for each job, the performance at the application server for providing with the application services may be decreased.